Continuing with the topic of gaining weight, why should you care if carbs seem to melt into thin air? It provides insights into your metabolism characteristics.
This topic can be a mini-series of tips alone, but simply, humans naturally operate at various resting metabolic levels, known as basal metabolic rate (BMR). Assuming all health indicators are normal, there are those people who will safely burn through pasta, pizza, bread, sweets, etc. with less chance of storing body fat.
Hand it to genetics! Interestingly, there is evidence that ties our ancestors' geographical origins to how we metabolize proteins, fats, and carbs...with carbs having the largest influence on body composition.
What's done is done! Your choices now are to add either muscle or fat. Though a few pounds of fat may add some fullness to your frame and look "OK", MUSCLE GAIN is preferred.
Even though you can get away with eating more carbs, including junk food, you want to concentrate on your protein and wholesome carb intake. Protein is the only macronutrient that builds muscle tissue, case closed! Furthermore, the carbs you do eat should be complex, nutrient-dense, and unaltered by Man.
Your meals should include quality protein, as the constant flow of amino acids will build new muscle tissue. ALERT: this is based on my assumption that you are strength training in order to give your body a REASON to add new muscle tissue.
Because carbs are friendlier to you, include portions of old-fashion oatmeal, brown rice, quinoa, yams, and other dense carbs. This strategy will allow your body to use the protein for muscle building while your fast metabolism burns through the carbs.
Maybe you don't necessarily have "fast metabolism", rather you simply don't eat enough. Have you conditioned yourself over the years to undereat, thereby keeping you skinny and "too thin"? Part 3 will discuss remedies to this dilemma.
Make it a great day!